1. Field of the Invention
This invention relates in general to earth boring and in particular to the way in which rotatable cutters are removably secured to raise or shaft drills used in the mining industry.
2. Background Information
The rotatable cutters of raise or shaft drill bits wear during drilling and are replaced periodically with new cutters on the original mounts of the bit body. Because of the large and destructive forces generated during earth drilling, it has been difficult to provide a mounting system that is not only rugged and reliable but also easy to manipulate quickly and easily by those who are responsible for replacing exhausted cutters. There have been a variety of proposed solution--some of significant commercial success--but the need for improvement subsists.